Elsevier, Tetrahedron Letters, 13(38), p. 2359-2362
DOI: 10.1016/s0040-4039(97)00348-1
Full text: Download
Regioselectivity and diastereoselectivity in the Michael addition of 2-phenylcyclohexanone to bulky α,β-unsaturated ketones can be controlled by carefully selecting the reaction conditions. Solvent-free solid-liquid PTC using tetrabutylammonium bromide as catalyst and potassium tertbutoxide as base leads to high de (up to 99%) of the 2,6-disubstituted regioisomer, which is, a priori, the unexpected isomer.